Brooklyn Center police shot and killed a 21-year-old autistic man Saturday afternoon while responding to a domestic disturbance call.

Officers were called to a home in the 5900 block of N. Halifax Avenue shortly after 4:20 p.m. on a report of a young man wielding a hammer and a knife who was fighting with his grandparents.

Soon after their arrival, officers reported “shots fired” inside the house.

“One down; we need paramedics here immediately,” an officer relayed to dispatchers, according to emergency audio. One officer suffered minor injuries during the struggle, authorities said.

Friends and relatives identified the man who was killed as Kobe Heisler. They say Heisler, who lived with his grandparents, was on the autism spectrum. He died at the scene.

Neighbors reported hearing an argument inside the home before police arrived. One nearby resident, who was painting at the time, said he could make out Heisler’s grandmother shouting, “Stop it.”

Minutes later, police entered the house and neighbors were startled by the pop of four to five gunshots.

A woman later identified as Heisler’s aunt drove up to the scene and sobbed as officers relayed the news. “How could this happen?” she cried out.

Other relatives gathered outside the yellow police tape to grieve, holding one another as they wept.

Zoey Seely, a next-door neighbor and longtime friend of Heisler’s, described him as a kind soul and said she’d never seen him become violent with anyone.

“I have no idea what could have prompted this,” she said. “I have to think something really triggered him.”

Heisler doesn’t appear to have a criminal record.

His grandparents, who are both in their mid-70s, were not hurt during the altercation. Property records show the couple have owned the home for nearly 50 years.

Late Saturday, officers were interviewing them at police headquarters.

Brooklyn Center Police Chief Tim Gannon said in a statement that responding officers were wearing their body cameras and have been placed on standard administrative leave.

The Minnesota Bureau of Criminal Apprehension has taken over the investigation — as is procedure following a deadly police shooting.